Integrated circuit with improved battery protection
US5159426A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 20, 1990 |
| Grant date | Oct 27, 1992 |
| Priority date | — |
| Expiry date | Dec 20, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D89/601
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A battery-backed integrated circuit, which receives battery power to maintain data (or logic states) when the system (external) power supply goes down. The battery power input is connected through a diode, so that the battery cannot be charged when the system power supply is active. The battery isolation diode is a junction diode, which is surrounded by a second junction. The battery junction collects minority carriers which will be generated when the battery protection diode is forward biased (i.e. when the integrated circuit is being powered from the battery). Otherwise, minority carriers can diffuse to other junctions, to cause leakage currents which can significantly degrade the lifetime of a low-powered device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.